<template>
    <nav>
        <ol class="pagination">
            <li :class="{'disabled': current == 1}"><a href="javascript:;" @click="setCurrent(current - 1)"> « </a></li>
            <li :class="{'disabled': current == 1}"><a href="javascript:;" @click="setCurrent(1)">首页</a></li>
            <li v-for="p in grouplist" :class="{'active': current == p.val}"><a href="javascript:;"
                                                                                @click="setCurrent(p.val)"> {{ p.text }} </a>
            </li>
            <li :class="{'disabled': current == page}"><a href="javascript:;" @click="setCurrent(page)"> 尾页 </a></li>
            <li :class="{'disabled': current == page}"><a href="javascript:;" @click="setCurrent(current + 1)"> »</a></li>
        </ol>
    </nav>
</template>

<script>
	//分页组件
  export default{
    data(){
      return {
        current: this.currentPage
      }
    },
    props: {
      total: {// 数据总条数
        type: Number,
        default: 0
      },
      display: {// 每页显示条数
        type: Number,
        default: 20
      },
      currentPage: {// 当前页码
        type: Number,
        default: 1
      },
      pagegroup: {// 分页条数
        type: Number,
        default: 5,
        coerce: function (v) {
          v = v > 0 ? v : 5;
          return v % 2 === 1 ? v : v + 1;
        }
      }
    },
    computed: {
      page: function () { // 总页数
        return Math.ceil(this.total / this.display);
      },
      grouplist: function () { // 获取分页页码
        var len = this.page, temp = [], list = [], count = Math.floor(this.pagegroup / 2), center = this.current;
        if (len <= this.pagegroup) {
          while (len--) {
            temp.push({text: this.page - len, val: this.page - len});
          };
          return temp;
        }
        while (len--) {
          temp.push(this.page - len);
        };
        var idx = temp.indexOf(center);
        (idx < count) && ( center = center + count - idx);
        (this.current > this.page - count) && ( center = this.page - count);
        temp = temp.splice(center - count - 1, this.pagegroup);
        do {
          var t = temp.shift();
          list.push({
            text: t,
            val: t
          });
        } while (temp.length);
        if (this.page > this.pagegroup) {
          (this.current > count + 1) && list.unshift({text: '...', val: list[0].val - 1});
          (this.current < this.page - count) && list.push({text: '...', val: list[list.length - 1].val + 1});
        }
        return list;
      }
    },
    methods: {
      setCurrent: function (idx) {
        if (this.current != idx && idx > 0 && idx < this.page + 1) {
          this.current = idx;
          this.$emit('pagechange', this.current);
        }
      }
    }
  }
</script>

<style scoped>
nav{
    margin: 0 10% 80px 10%;
}
ol.pagination {
    margin: 0;
    padding: 0;
    list-style-type: none;
}
ol.pagination li{
    float: left;
    margin-right: 0.6em;
}
ol.pagination li a{
    color:black;
    border-radius: 5px 5px;
    display: block;
    padding: 0.2em 0.5em;
    /* border: 1px solid #ccc; */
    text-decoration: none;
}
ol.pagination a:hover,
ol.pagination a:focus {
    background-color:rgb(45, 60,75);
    color: white;
}
ol.pagination a[rel="prev"],
ol.pagination a[rel="next"]{
    border: none;
}
</style>